The Mining Industry’s Role in Enhanced Weathering and Mineralization for CO₂ Removal

Abstract

Enhanced weathering and mineralization (EWM) aim to remove carbon dioxide (CO 2 ) from the atmosphere by accelerating the reaction of this greenhouse gas with alkaline minerals. This suite of geochemical negative emissions technologies has the potential to achieve CO 2 removal rates of >1 gigatonne per year, yet will require gigatonnes of suitable rock. As a supplier of rock powder, the mining industry will be at the epicenter of the global implementation of EWM. Certain alkaline mine wastes sequester CO 2 under conventional mining conditions, which should be quantified across the industry. Furthermore, mines are ideal locations for testing acceleration strategies since tailings impoundments are contained and highly monitored. While some environmentally benign mine wastes may be repurposed for off-site use� reducing costs and risks associated with their storage�numerous new mines will be needed to supply rock powders to reach the gigatonne scale. Large-scale EWM pilots with mining companies are required to progress technology readiness, including carbon verification approaches. With its knowledge of geological formations and ore processing, the mining industry can play an essential role in extracting the most reactive rocks with the greatest CO 2 removal capacities, creating supply chains, and participating in lifecycle assessments. The motivations for mining companies to develop EWM include reputational benefits and carbon offsets needed to achieve carbon neutrality.

Parts-Per-Million Carbonate Mineral Quantification with Thermogravimetric Analysis–Mass Spectrometry

“…In addition to building off the success of Kemp et al and applying TGA–MS studies to carbonate mineralization applications, our present study was also motivated by the need to identify and quantify complex polymer mixtures found in environmental microplastics. − The approach detailed in this study demonstrates a method for double-digit parts-per-million carbonate quantification that can be applied to both natural and engineered low-carbon materials. This approach may especially assist carbon crediting efforts for CO 2 direct air capture (DAC) materials, , enhanced weathering, mine tailings carbonation, − and in situ mineralization projects, spur developing research on carbon curing in cement, − allow for new levels of identification of trace environmental contaminants, and support advancements in materials science.…”

Microtextural Characteristics of Ultramafic Rock-Forming Minerals and Their Effects on Carbon Sequestration

“…It is also worth exploring another alternative option for carbon removal. Enhanced rock weathering (ERW) is one of the attractive engineered practices to speed up the natural CO2 removal from the air [2,7,19,[33][34][35][36]. The technique involves increasing surface areas of CO2-reactive rocks by finely grinding methods and then applying the rock powder over lands, coasts, or in the oceans [8,35,[37][38][39].…”

“…The technique involves increasing surface areas of CO2-reactive rocks by finely grinding methods and then applying the rock powder over lands, coasts, or in the oceans [8,35,[37][38][39]. Selecting suitable rock types for ERW is very important in maximizing the reaction rates and ultimately offering the greatest CO2 uptake capacity [10,36,40,41]. In addition to rock types, the abundance of rock resources essentially yields unlimited capacity for CO2 sequestration.…”